For many decades, viewing disks of the type that can be viewed by stereoscopic viewing devices have been very popular. This type of disk is made of stiff opaque sheet material and is formed with 14 substantially-rectangular apertures which are equiangularly spaced about, and are equidistant from, the center of the disk. The disk encompasses seven pairs of transparencies, representing left and right stereoscopic images respectively of seven scenes. The stereoscopic viewing device has two eyepieces for viewing simultaneously, with both eyes respectively, one pair of transparencies so that the user can view a three-dimensional image. The viewing device includes an advancing mechanism which engages indexing holes in the disk for rotating the disk to seven indexed positions allowing the user to view three-dimensional images of the seven scenes in succession.
In the traditional method of mass manufacturing a three-dimensional viewing disk, a stereo camera is used to capture left eye and right eye images of a scene on photographic transparency film. The transparency film is then used to generate corresponding internegatives and the two internegatives of one pair are mounted on a carrier in carefully controlled relative positions and orientations. The carrier is placed in an optical printer which makes multiple copies of the left eye image and multiple copies of the right eye image on respective rolls of receiving film. The carrier serves to position the internegatives precisely relative to the frame of the receiving film, and accordingly the images are located with a high degree of precision relative to the frame of the receiving film. The rolls of receiving film are die cut into individual transparencies and the left and right eye transparencies for a given scene are attached to a first of the two cards using registration elements to ensure that the two die cut transparencies are in the proper relative positions and orientations. The left and right eye transparencies for the next scene are then attached to the first card, and so on until all seven pairs of transparencies have been attached to the first card. Finally, the second card is attached to the first card and the 14 transparencies are then held securely between the cards.
The traditional method of fabricating a three-dimensional viewing disk requires complex machinery which must be maintained and adjusted to ensure that the die-cut transparencies will be properly positioned in the completed disk. The cost per disk of manufacturing a long run of disks is very low, but the nature of the manufacturing process makes it expensive to manufacture a short run of disks. Further, the lead time required to obtain a short run of disks is long. Therefore, this method of manufacturing is not economically feasible for short runs of disks such as those in the range of 1 to 150 disks.
A more practical approach to manufacturing short runs of three-dimensional viewing disks uses computer technology, rather than mechanical technology, to position the images within a template for a disk. The method allows a short run of viewing disks to be manufactured at a substantially lower cost per disk than the conventional method of manufacturing three-dimensional viewing disks. Such a method makes the process practicable for customized viewing disks that are suitable for uses such as promotional activities for businesses.
One method, which is described in U.S. Pat. No. 6,295,067, comprises creating first and second image data files representing the left and right stereoscopic images respectively of the selected scene, employing the first and second image data files to create a stereo image data file representing the left and right stereoscopic images in predetermined relative positions, and employing the stereo image data file to create a transparency image incorporating the left and right stereoscopic images. The left and right stereoscopic images of the selected seven scenes are placed in appropriate relative orientations and positions in a graphics plane using graphic arts software such as Adobe Photoshop and Adobe Illustrator to create digital image files that are printed onto a master transparency film using a film recorder. Duplicate transparencies are created by a contact printing process, laminated with transparent laminate material, and then punched to create the three-dimensional viewing disks. Although this method is commercially viable for manufacturing short runs of disks, it does require a human operator to position the image files within templates and make adjustments to the relative positions of images to achieve the desired stereoscopic effect. As such, the method is not particularly suitable for Internet-based businesses that are directed towards consumers as opposed to businesses. Thus there is a need for a method of manufacturing three-dimensional viewing disks that avoids the necessity of human-directed processing of the images with graphic arts software.